Systems for automated capture and recovery of oil from oil-contaminated water and solids

ABSTRACT

Systems for automated capture and recovery of oil from oil-contaminated water and solids are disclosed. In some embodiments, the systems include the following: a plurality of automated robotic oil recovery units; a plurality of deployable oil collection membranes positioned within each of the units, each of the membranes including an upper half including a material impermeable to both water and crude oil and a lower half including a semi-permeable hydrophilic membrane that is permeable to water but impermeable to crude oil; and a high pressure carbon dioxide oil solids separation unit for separating oil from oil-contaminated solids thereby producing substantially oil-free solids and an oil and carbon dioxide mixture; a solids separation unit for the separating substantially oil-free solids from the oil and carbon dioxide mixture via gravity separation; and an oil separation unit for separating oil from the oil and carbon dioxide mixture using a pressure swing.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of U.S. Provisional Application No.61/521,300, filed Aug. 8, 2011, which is incorporated by reference as ifdisclosed herein in its entirety.

BACKGROUND

While the number of major oil tanker spills has decreased significantlyin the last decade due to safer shipping lanes and better engineereddouble hulls, crude oil spills in the marine environment continue to bea major environmental, political, and economic issue. Other large-scaleoil spills such as the BP oil accident in 2010 can also be consideredunder the same category. Traditional methods of oil spill cleanupinclude in situ burning, containment using booms and skimmers, anddilution with chemical dispersants. Not only are these methodsinefficient in that they require significant amounts of time andmanpower, they themselves often lead to significant environmental damageeither through the release of significant greenhouse gases or toxicchemicals.

Current oil spill cleanup technologies have the followingshortcomings: 1. Cleanup cannot keep up with the rate of the oil spillleading to large area of contamination; 2. Require large amount of timeand manpower; 3. Cannot recover most of the collected oil (absorbentsare landfilled—another environmental problem).

However, even in recent years where little crude oil was spilled, suchas in 2004, over 25,000 tonnes of crude oil were spilled and damaged themarine environment. The majority of crude oil spilled in a yeartypically derives from a major crude oil spill in which more than 1000barrels are spilt.

According to the National Oceanic and Atmospheric Administration's(NOAA) Emergency Crude Oil Spill Response website, marine oil spills caninvolve many types of fuels, ranging from refined liquid petroleum fromships and recreational vessels to crude oil from tankers and offshorerigs. Of these fuels, crude oil poses the largest threat to theenvironment, as crude oil poisons and damages the flora and fauna of themarine ecosystem. It can become embedded in the sand and mud ofshorelines, lasting for years after the spill occurred.

Apart from the long lasting environmental impacts, crude oil spills mustbe dealt with swiftly and effectively because crude oil spills result inpolitical tension between environmental groups, the government, andcrude oil companies. Crude oil spills also introduce major economiclosses and public image damage to both crude oil companies and coastalcommunities.

NOAA's website gives descriptions of the current off shore crude oilspill cleanup technologies designed to meet the following primaryobjectives: (a) Prevent the spill from moving onto shore; (b) Reduce theimpact of crude oil on marine life; and (c) Speed the degradation of anyunrecovered crude oil.

For open-water crude oil spills, if weather permits, booms are used totemporarily contain crude oil between the surface and up to a few feetbelow the surface with special nets that do not allow crude oil to passthrough. However, wave action renders booms highly ineffective.

Skimmers outfitted with pumps on board emergency boats are often used toclean up oil contained in booms. These skimmers usually employ suctionpumps to intake surface crude oil. The crude oil is then stored inunderwater tanks. Skimmers are only effective in calm waters, though,and are limited by the power-draining pumps and heavy tanks. Analternative to the pump is a skimmer that contains an oil-absorbingcloth. The cloth is dragged along the surface and oil is squeezed out ofit when the cloth is saturated. Therefore, oil can be recovered.Nonetheless, the process of squeezing out the oil is very energyintensive. While the cloths can be reused, their capacity to collect oilis greatly reduced with each use. Furthermore, the used, oily cloth mustbe land filled after use, presenting an environmental concern.

Controlled burns of the oil slick within booms are also very common.They are relatively effective, however this process releases massiveamounts of carbon dioxide and none of the crude oil can be recovered.

Chemical dispersants sprayed from aircraft or emergency ships onto thearea of containment is a method used to break up crude oil surfaceslicks. The breakup of crude oil helps microbes to digest the crude oilfaster and prevents crude oil slicks from poisoning and coating marinewildlife which inhabit or breathe at the ocean surface. The chemicalproperties and environmental effects of dispersants however, are notfully understood, and may be as detrimental to the marine environment asthe crude oil itself. Furthermore, dispersants often exacerbate thespreading of crude oil over a large area and depth, especially whenstronger currents are present. None of the crude oil can be recovered.

All of these cleanup methods are problematic in that they are highlylabor intensive since they require manual deployment/coordination andmay require specially trained technicians. In addition, theirimplementation and transport to the spill site often takes a significantamount of time since they arrive via emergency ships, which may not benear the spill. This time lag allows the oil to spread great distances,increasing the likelihood of shoreline oiling and contact with themarine environment. The spreading also makes cleanup more difficultsince a greater area must be treated.

SUMMARY

Embodiments of the disclosed subject matter include oil spill cleanupsystems that include self-powered automated oil recovery robotic unitsand a soil cleaning system that uses carbon dioxide as a leaching media.

In systems according to the disclosed subject matter, the self-poweredautomated oil recovery robotic units are kept on board a tanker ship,similar to life boats. They are designed with solar panels so that theycan store solar energy for the emergency situations. Duringnon-emergency times, the generated excess energy is used for theoperation of the tanker ships. If there is an oil spill, theself-powered automated oil recovery robotic units are deployed tocollect and capture oil using special membranes until they can berecovered. Therefore, the crew can focus on the repair of the tankership or other emergency related activities. The collected oil is thenpumped into a new tanker once it arrives to the spill site. Componentsof the robotic units, i.e., the membranes, are easily cleaned andrecycled.

Oil spill cleaning technology according to the disclosed subject matteris designed to clean the contaminated soil using high pressure carbondioxide. Since liquid or supercritical carbon dioxide is miscible withoil, carbon dioxide will separate oil from the particle surface. Onceoil is leached out, the soil/sand can be separated via gravityseparation. The separation of oil and carbon dioxide is easy sincecarbon dioxide can be vaporized by lowering the pressure. In fact, asmaller pressure swing can also be used to keep carbon dioxide in liquidphase and recycle it through the cleaning system. With both the roboticunits and the cleaning system, oil can be recovered in a useable forminstead of being landfilled.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings show embodiments of the disclosed subject matter for thepurpose of illustrating the invention. However, it should be understoodthat the present application is not limited to the precise arrangementsand instrumentalities shown in the drawings, wherein:

FIG. 1 is a schematic diagram of systems according to some embodimentsof the disclosed subject matter;

FIG. 2 is a side section view of an automated robotic oil recovery unitsaccording to some embodiments of the disclosed subject matter;

FIG. 3 is a back section view of an automated robotic oil recovery unitsaccording to some embodiments of the disclosed subject matter; and

FIG. 4 is a side section view of an automated robotic oil recovery unitaccording to some embodiments of the disclosed subject matter.

DETAILED DESCRIPTION

Referring now to FIGS. 1-4, aspects of the disclosed subject matterinclude a system 100 for cleaning oil spills, which includes a pluralityof automated robotic oil recovery units 102 and a solids cleaning module104.

Referring now to FIGS. 1 and 2, each of automated robotic oil recoveryunits 102 includes deployable membranes 106 for collecting oil 108 andeach of the units is configured for deployment from a ship 110 forautomated capture and recovery of oil from oil-contaminated water 112and solids 114. In some embodiments, system 100 will include units 102of varying sizes.

Referring now to FIGS. 3 and 4, in some embodiments, deployablemembranes 106 include an upper half 116 including a material 118impermeable to both water 120 and crude oil 108, e.g., HDPE or similar,and a lower half 124 including a semi-permeable hydrophilic membrane 126that is permeable to water 120 but impermeable to crude oil 108, e.g.,as disclosed in published U.S. Patent Application US2011/0303620, by Dr.Di Gao, which is incorporated by reference as if disclosed herein in itsentirety.

Referring now to FIGS. 1-4, each of units 102 include an outer shell 128having a shock-absorbing lining 130 for protecting inner components ofthe units from forces generated by impact on water when deploying theunits from ship 110 and from corrosion from seawater 132. Outer shell128 includes a plurality of channels 134 formed on an inner surface 136of the outer shell. Channels 134 are configured to allowoil-contaminated water 112 to flow through units 102 and keep membranes106 open when stored in outer shell 128. Each of units 102 includes amembrane deployment track 138 for deploying membranes 106 one by one andholding one end of a membrane in place while collecting oil 108.

Referring now to FIG. 4, each of units 102 includes inflatable membranesupports 140 for keeping membranes 106 floating on the surfaces 142 ofwater 132 and visible to collection vessels. Each of units 102 alsoinclude deployable inflatable body supports 144 and air tanks 146 forinflating the inflatable body supports and inflatable membrane supports140.

Referring now to FIGS. 2-4, each of units 102 include a power unit 148including a motor 150, one or more batteries 152, a propeller unit 154,and a gas tank 156. Power unit 148 is contained in a substantiallywaterproof storage compartment 158 formed within shell 128. Each ofunits 102 also includes solar panels 160 for charging batteries 152.Each of units 102 includes a protective mesh 162 for preventing seaweedand other debris from entering the units and damaging propeller unit154.

Referring now to FIG. 1, in some embodiments, system 100 includes aplurality of booms 164 connected to automated robotic oil recovery units102 thereby allowing the units to form a ring of booms for containing anoil spill. In some embodiments, a hollow boom, which includes pumpsembedded along its circumference, can be used.

Referring now to FIG. 2, each of units 102 includes a GPS control unit166 for coordinating positions of each of the plurality of automatedrobotic oil recovery units of the system around an oil spill andidentifying its position when it needs to be recovered. In someembodiments, GPS control unit 166 includes an antenna 168.

Referring again to FIG. 1, although not illustrated in detail, solidscleaning module 104, which is used for separating and recovering oilfrom oil-contaminated solids that are captured by automated robotic oilrecovery units 102, include the following: a high pressure carbondioxide oil solids separation unit for separating oil fromoil-contaminated solids thereby producing substantially oil-free solidsand an oil and carbon dioxide mixture; a solids separation unit for theseparating substantially oil-free solids from the oil and carbon dioxidemixture via gravity separation; and an oil separation unit forseparating oil from the oil and carbon dioxide mixture using a pressureswing.

Systems according to the disclosed subject matter offer advantages andbenefits over known technology. A large scale oil spill causes greateconomic damage to companies. Thus, there is a significant commercialneed for a technology that minimizes environmental issues related topotential spills. Thus, like a having an airbag in your car, theinstallation of oil spill cleanup devices according to the disclosedsubject matter will lower the insurance for the tankers and providebetter environmental measures for the companies.

Self-powered on-board robotic system according to the disclosed subjectmatter offer the following advantages over known systems: 1. Cleanup cankeep up with the rate of the oil spill leading to limited area ofcontamination; 2. Require minimum amount of time and manpower; and 3.Can recover most of the collected oil (no landfill needed).

High pressure carbon dioxide soil/sand cleaning systems according to thedisclosed subject matter offer the following advantages over knownsystems: 1. Can recover most of the collected oil (no landfill needed);2. Mobile unit (can be installed at the back of a truck)—can clean upspills at various locations; and 3. Save environment. Systems usingcarbon dioxide as a leaching medium are also used for any otherenvironmental contaminations associated with soil, sand, or particles.

Although the disclosed subject matter has been described and illustratedwith respect to embodiments thereof, it should be understood by thoseskilled in the art that features of the disclosed embodiments can becombined, rearranged, etc., to produce additional embodiments within thescope of the invention, and that various other changes, omissions, andadditions may be made therein and thereto, without parting from thespirit and scope of the present invention.

What is claimed is:
 1. A system for cleaning oil spills, comprising: aplurality of automated robotic oil recovery units, each of said unitsincluding deployable membranes for collecting oil and each of said unitsconfigured for deployment from a ship and for automated capture andrecovery of oil from oil-contaminated water and solids; and a solidscleaning module for separating and recovering oil from oil-contaminatedsolids.
 2. The system according to claim 1, wherein each of saiddeployable membranes comprise: an upper half including a materialimpermeable to both water and crude oil; and a lower half including asemi-permeable hydrophilic membrane that is permeable to water butimpermeable to crude oil.
 3. The system according to claim 1, whereineach of said plurality of automated robotic oil recovery units comprise:an outer shell including a shock-absorbing lining for protecting innercomponents of said system from forces generated by impact on water whendeploying said system from a ship and from corrosion from seawater; aplurality of channels formed on an inner surface of said outer shell,said channels configured to allow oily water to flow through said systemand keep said membranes open when stored in said shell;
 4. The systemaccording to claim 1, further comprising: a plurality of inflatablemembrane supports for keeping said membranes floating on the surfaces ofthe water and visible to collection vessels; a plurality of deployableinflatable body supports; and air tanks for inflating said inflatablebody supports and said inflatable membrane supports.
 5. The systemaccording to claim 3, further comprising: a power unit including amotor, a battery, a propeller unit, and a gas tank; and a substantiallywaterproof storage compartment formed within said shell that includessaid power unit.
 6. The system according to claim 5, further comprisingsolar panels for charging said batteries.
 7. The system according toclaim 1, further comprising a membrane deployment track for deployingsaid membranes one by one and holding one end of a membrane in placewhile collecting oil.
 8. The system according to claim 5, furthercomprising a protective mesh for preventing seaweed and other debrisfrom entering said system and damaging said propeller unit.
 9. Thesystem according to claim 1, further comprising a GPS control unit forcoordinating positions of each of said plurality of automated roboticoil recovery units of said system around an oil spill and identifyingits position when it needs to be recovered.
 10. The system according toclaim 1, said solids cleaning module further comprising: a high pressurecarbon dioxide oil solids separation unit for separating oil fromoil-contaminated solids thereby producing substantially oil-free solidsand an oil and carbon dioxide mixture; a solids separation unit for saidseparating substantially oil-free solids from said oil and carbondioxide mixture via gravity separation; and an oil separation unit forseparating oil from said oil and carbon dioxide mixture using a pressureswing.
 11. The system according to claim 1, further comprising: aplurality of booms configured to connect to said plurality of automatedrobotic oil recovery units thereby allowing said units to form a ring ofbooms for containing an oil spill.
 12. A system for automated captureand recovery of oil from oil-contaminated water and solids, comprising:a plurality of automated robotic oil recovery units; a plurality ofdeployable oil collection membranes positioned within each of saidunits, each of said membranes including an upper half including amaterial impermeable to both water and crude oil and a lower halfincluding a semi-permeable hydrophilic membrane that is permeable towater but impermeable to crude oil; and a solids cleaning module forseparating and recovering oil from oil-contaminated solids.
 13. Thesystem according to claim 12, further comprising: a plurality ofinflatable membrane supports for keeping said membranes floating on thesurfaces of the water and visible to collection vessels.
 14. The systemaccording to claim 12, further comprising a GPS control unit forcoordinating positions of each of said plurality of automated roboticoil recovery units of said system around an oil spill and identifyingits position when it needs to be recovered.
 15. The system according toclaim 12, said solids cleaning module further comprising: a highpressure carbon dioxide oil solids separation unit for separating oilfrom oil-contaminated solids thereby producing substantially oil-freesolids and an oil and carbon dioxide mixture; a solids separation unitfor said separating substantially oil-free solids from said oil andcarbon dioxide mixture via gravity separation; and an oil separationunit for separating oil from said oil and carbon dioxide mixture using apressure swing.
 16. The system according to claim 12, furthercomprising: a plurality of booms configured to connect to said pluralityof automated robotic oil recovery units thereby allowing said units toform a ring of booms for containing an oil spill.
 17. A system forautomated capture and recovery of oil from oil-contaminated water andsolids, comprising: a plurality of automated robotic oil recovery units;a plurality of deployable oil collection membranes positioned withineach of said units, each of said membranes including an upper halfincluding a material impermeable to both water and crude oil and a lowerhalf including a semi-permeable hydrophilic membrane that is permeableto water but impermeable to crude oil; and a high pressure carbondioxide oil solids separation unit for separating oil fromoil-contaminated solids thereby producing substantially oil-free solidsand an oil and carbon dioxide mixture; a solids separation unit for saidseparating substantially oil-free solids from said oil and carbondioxide mixture via gravity separation; and an oil separation unit forseparating oil from said oil and carbon dioxide mixture using a pressureswing.
 18. The system according to claim 17, further comprising: aplurality of inflatable membrane supports for keeping said membranesfloating on the surfaces of the water and visible to collection vessels.19. The system according to claim 17, further comprising a GPS controlunit for coordinating positions of each of said plurality of automatedrobotic oil recovery units of said system around an oil spill andidentifying its position when it needs to be recovered.
 20. The systemaccording to claim 17, further comprising: a plurality of boomsconfigured to connect to said plurality of automated robotic oilrecovery units thereby allowing said units to form a ring of booms forcontaining an oil spill.